Bug #913: mathn e$B$7$?>l9g!"e(Bsqrt(NaN) e$B$,J#AG?t$K$J$ke(B
http://redmine.ruby-lang.org/issues/show/913
e$B5/I<<Te(B: tadayoshi funaba
e$B%9%F!<%?%9e(B: Open, e$BM%@hEYe(B: Normal
main@191-20081221> nan = 0.0/0
#=> NaN
main@191-20081221> Math.sqrt(nan)
#=> NaN
main@191-20081221> require ‘mathn’
#=> true
main@191-20081221> Math.sqrt(nan)
#=> (0+NaN*i)